A pipe joint with which a pipe is inserted into a joint hole of a joint body and then a nut is screwed into the joint body to connect the pipe to the joint hole of the joint body has been known as a pipe joint used for joining of a pipe through which fluid is made to flow into a refrigerant pipe of a refrigeration device, for example. A flareless joint as disclosed by a prior art of Japanese Laid-Open Patent Publication No. 2003-74768 has been frequently adopted as the pipe joint as described above. According to this flareless joint, when a nut is screwed into a joint body, a sleeve is interposed between the joint body and the nut, and the sleeve bites into the outer periphery of the pipe by the screwing, thereby ensuing the sealing performance of the joint portion between the pipe and the joint body.
FIG. 16 shows the flareless joint disclosed in the prior art of Japanese Laid-Open Patent Publication No. 2003-74768. This flareless joint is constructed by a joint body 101, a nut 102, and a sleeve 103 provided between the joint body 101 and the nut 102. When the pipe 104 is joined to the joint body 101, the sleeve 103 is mounted on the outer peripheral surface 104a of the pipe 104. The distal portion 104b of the pipe 104 is inserted into a joint hole 101a of the joint body 101, and the threaded portion 102a of the nut 102 is engaged with the threaded portion 101b of the joint body 101. At this time, the proximal end face 103a of the sleeve 103 receives pressing force from a pressing face 102b of the nut 102, and the distal portion 103b of the sleeve 103 receives pressing force from a taper face 101c of the joint body 101. Therefore, the distal portion 103b of the sleeve 103 bites into the outer peripheral surface 104a, and the pipe 104 of the pipe 104 is connected to the joint hole 101a of the joint body 101. As described above, the flareless joint ensures the sealing performance of the joint portion between the pipe 104 and the joint body 101 by the biting of the sleeve 103 into the pipe 104.